If you’ve ever heard Abbott and Costello‘s famous “Who’s on first?” routine, you can understand how confusing it can be when people haven’t agreed on a common meaning for the words and phrases they use to communicate with each other.

A similar situation can occur in scientific discussions, but the results aren’t quite as funny. When time, money and professional reputations are on the line, it is critical that people have the same understanding of key words and concepts.

Researchers continue to dive into the impact of sedentary behavior on our health and productivity, but without consistent terminology and definitions, it’s challenging to compare study findings and applications. For instance, what one scientist calls physical inactivity another scientist may consider sedentary. Until now.

The Sedentary Behavior Research Network (SBRN) recently released the results of a terminology consensus project, which defines 10 movement-based terms. Terms like physical inactivity, stationary behavior and sedentary behavior now have approved definitions, as well as caveats and specific examples.

One of the more recent terms used often in our digital age is screen time, which researchers define as time spent on screen behaviors that are not related to school or work. They then break this down into recreational, stationary, sedentary and active screen time. Examples include watching TV and using a smart device.

These definitions combined with an illustration around movement behaviors in a 24-hour period, serve as a foundation for educating fellow researchers, employees and employers on the definitions and the negative impact of sedentary behaviors.

So now we’ll all know when Sedentary is on first and Stationary is on second.